Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
Digital cameras have surpassed film based cameras as a means for capturing images. In addition to digital cameras that capture images, there are also numerous software products that can modify digital images or create new images containing graphics or other information. The ability to capture or create images and store them electronically has lead to wide spread use of digital images in computer applications and on the Internet.
A traditional digital image comprises image data that represents pixel data for the original image and is organized and stored in a computer file. The image data is organized according to one of a number of different image formats created to store digital image data. JPEG and GIF formats are examples of standardized image formats that are commonly used by computer applications and on the Internet. JPEG is an acronym for the Joint Photographic Experts Group which created a standard that defines the image format. Images stored in this format have a file name that use the extension “JPG” to identify the type of image format used to store the image. GIF is an acronym for Graphics Interchange Format and was introduced by CompuServe. Images stored in this format have a file name that use the extension “GIF” to identify the type of image format used to store the image.
Many different digital image formats have been defined and each has certain characteristics and advantages that are typically related to their ability to reduce or compress the image data prior to storage. To reduce storage requirements, it is common for image formats to specify the use of one or more compression algorithms that reduce the amount of the image data required prior to storage. The stored image data must then be decompressed prior to being rendered for display or printing. Compression algorithms are generally classified as either lossless, that is they can recover all data removed during the compression process, or lossy, that is they are not able to fully recover data removed during the compression process.
Before a digital image can be displayed on a user display or printed, the digital image data must be rendered. Rendering a digital image is a process that recreates, as accurately as possible, image data for the original image from the stored image data. The recreated image data is in a form that can be easily displayed for viewing or printed. Web browsers, e-mail clients and other software applications that display or print digital images use software known as a rendering engine to render the digital image for viewing or printing.
The electronic image formats have at least one thing in common; they define how to store and recover one or more still digital images. The still images are static in that the elements of each image are reproduced, as faithfully as the image format allows, each time the image is rendered. Additionally, while each image format requires processing to recover the image, the type of processing is well know for each image format and the rendering engine of each application includes program code to process each supported image format to recover the image.
One area that uses digital images is product coupons. Product coupons are used to reduce the price of goods or services. For example, a company may offer a coupon that provides 10% off one of the company's products as a promotion. Before digital images, coupons were printed and distributed to customers in newspapers, flyers and magazines. Companies only accepted original printed coupons so the quantity of coupons was known and limited. This meant the maximum cost for redeeming the coupons could be calculated because the quantity was known.
However, it is now common to distribute coupons as a digital image using email, web sites, text messages, social media and others channels. With digital coupons, the quantity of coupons cannot be controlled because a digital coupon can be electronically copied and redistributed any number of times. Additionally, a person can print a single digital coupon multiple times and use the coupons to reduce the price of the associated product or service to or close to zero. This circumvents the intended promotional purpose of a coupon.
In another application, airports or other types of transportation terminals have started using electronic boarding passes to allow passengers to gain access to areas of a terminal restricted to confirmed passengers. An electronic boarding pass typically includes a bar code stored as a digital image that is electronically sent to an electronic device registered to a passenger after the passenger has completed a check-in process. The bar code is encoded with information unique to the passenger and only intended to be used by the passenger. However, because it is a digital image, copies can be forwarded to other people creating security issues.
Another issue is enforcing copyright restrictions on digital images. Once a digital image can be viewed on an electronic device, there is little that can be done to stop improper copying of the image. Placing a visible copyright notice on an image does little to stop people from copying the image and placing a copyright notice in the image data file also does not stop people from copying the image.
Therefore, for the above reasons and others, there is a need for a new digital image format that provides additional functions beyond simply reproducing a stored digital image and that can control copying a digital image.